A fishing reel contains a drive force transmission mechanism that includes a rotational shaft, a drive gear, bearings rotatably supporting these elements, and a clutch, and a fishing reel is used in an environment where dust and moisture tend to penetrate internal parts. Therefore, it has been proposed to build in a magnetic fluid sealing device such as disclosed in Japanese Patent Application Publication No. 2010-187566 (hereinafter “the '566 Publication”) to protect primary constituents. In the '566 Publication, the magnetic fluid sealing device is disposed in an opening portion of a housing cavity in a reel body in which a one-way clutch is provided. A magnetic fluid retained between the reel body and a drive portion (a pinion) prevents dust and moisture from penetrating the one-way clutch.
The rotational shaft in a fishing reel is typically supported with ball bearings in order to improve rotation performance of the rotational shaft. The ball bearings contain multiple rolling elements (rolling members) circumferentially arranged between inner and outer rings. Such bearings are susceptible to penetration of foreign substances such as dust and moisture through a gap between the inner and outer rings, and thus it has been proposed to seal the bearings with a magnetic fluid as disclosed in Japanese Patent Application Publication No. 2013-228044, for example.
In a fishing reel including the magnetic fluid sealing device and the magnetic fluid sealed bearings mentioned above, penetration of dust and moisture can be effectively prevented if it is used normally. However, when the fishing reel is dropped into water or when the fishing reel is washed with tap water or showered after use, water flowing on a polar plate penetrates the magnetic fluid portion and acts to remove the magnetic fluid. This action reduces the amount of the magnetic fluid, and as a result, the waterproofness cannot be retained for a long period.